Adam Lamberthad harsh criticism for the musical drama Les Miserables over the weekend -- and the film's starRussell Crowe is on his side.

On Sunday, Dec. 30, the American Idol alum slammed the singing in the Tom Hooper-directed film. "Les Mis: Visually impressive with great emotional performances. But the score suffered massively with great actors pretending to be singers. It's an opera. Hollywood's movie musicals treat the singing as the last priority. (Dreamgirls was good.)" Lambert, 30, tweeted. "And I do think it was cool they were singing live -- but with that cast, they should have studio recorded and sweetened the vocals."

Oscar-winning actor Crowe, 48, who stars as Javert in the film, responded to Lambert's criticism on Twitter Jan. 1. "I don't disagree with Adam," he wrote. "Sure, it could have been sweetened. Hooper wanted it raw and real, that's how it was."

Lambert did have some nice words to say for the film, but they weren't directed at Crowe.

"Anne Hathaway as Fantine and [Aaron Tveit's] Enjolras were the exceptions for me," he tweeted of the performances. "Helena B Carter and Sasha B Cohen were great too . . . Eponine's voice was cool too."

But overall, Lambert wasn't a fan of the casting in the film. He argued, "The industry will say 'these actors were so brave to attempt singing this score live,' but why not cast actors who could actually sound good?"

"Sorry for being so harsh but it's so True!" he added. "One more clarification: Do go see it for Anne Hathaway's performance. It's was breathtaking."